Revisiting host identification of bacteriophage Enc34: from biochemical to molecular.

In our 2012 genome announcement (J Virol 86:11403-11404, 2012, https://doi.org/10.1128/JVI.01954-12), we initially identified the host bacterium of bacteriophage Enc34 as Enterobacter cancerogenus using biochemical tests. However, later in-house DNA sequencing revealed that the true host is a strain of Hafnia alvei. Capitalizing on our new DNA-sequencing capabilities, we also refined the genomic termini of Enc34, confirming a 60,496-bp genome with 12-nucleotide 5' cohesive ends. IMPORTANCE: Our correction reflects the evolving landscape of bacterial identification, where molecular methods have supplanted traditional biochemical tests. This case underscores the significance of revisiting past identifications, as seemingly known bacterial strains may yield unexpected discoveries, necessitating essential updates to the scientific record. Despite the host identity correction, our genome announcement retains importance as the first complete genome sequence of a Hafnia alvei bacteriophage.

The impact of Hafnia alvei HA4597™ on weight loss and glycaemic control after bariatric surgery - study protocol for a triple-blinded, blocked randomized, 12-month, parallel-group, placebo-controlled clinical trial.

BACKGROUND: Subjects with obesity exhibit changes in gut microbiota composition and function (i.e. dysbiosis) that contribute to metabolic dysfunction, including appetite impairment. Although bariatric surgery is an effective treatment for obesity with a great impact on weight loss, some subjects show weight regain due to increased energy intake after the surgery. This surgery involves gut microbiota changes that promote appetite control, but it seems insufficient to completely restore the obesity-associated dysbiosis - a possible contributor for weight regain. Thus, modulating gut microbiota with probiotics that could improve appetite regulation as a complementary approach to post-operative diet (i.e. Hafnia alvei HA4597™), may accentuate post-surgery weight loss and insulin sensitivity. METHODS: This is a protocol of a triple-blinded, blocked-randomized, parallel-group, placebo-controlled clinical trial designed to determine the effect of Hafnia alvei HA4597™ supplementation on weight loss and glycaemic control 1 year after bariatric surgery. Patients of Hospital CUF Tejo, Lisbon, that undergo Roux-en-Y gastric bypass are invited to participate in this study. Men and women between 18 and 65 years old, with a BMI ≥ 35 kg/m2 and at least one severe obesity-related comorbidity, or with a BMI ≥ 40 kg/m2, and who are willing to take 2 capsules of Hafnia alvei HA4597™ probiotic supplements (equivalent to 5 × 107 CFU) vs. placebo per day for 90 days are included in this study. Assessments are carried out at baseline, 3, 6, 9, and 12 months after the surgery. Loss of weight in excess and glycated haemoglobin are considered primary outcomes. In addition, changes in other metabolic and inflammatory outcomes, gut microbiota composition and metabolites, as well as gastrointestinal quality of life are also being assessed during the trial. DISCUSSION: The evidence obtained in this study will provide relevant information regarding the profile of the intestinal microbiota of individuals with severe obesity and the identification of the risk/benefit ratio of the use of Hafnia alvei HA4597™ as an adjunctive treatment in the maintenance of metabolic and weight control one year after the surgical intervention. TRIAL REGISTRATION: ClinicalTrials.gov NCT05170867. Registered on 28 December 2021.

[Rare Cause of Lung Tumour - Pulmonary Infection with Hafnia alvei: A Case Report]. / Seltene Ursache eines Lungentumors ­ Fallbericht einer pulmonalen Infektion mit Hafnia alvei.

If a malignant disease is suspected, rapid diagnosis of suspicious pulmonary masses is required. In the presented case, malignancy was repeatedly not proven. Only the test-appropriate antibiotic treatment of an intestinal germ that was initially assessed as an impurity brought the therapeutic success with total remission. In our case the treatment with broad-spectrum penicillin piperacillin/tazobactam was ineffective and only the gyrase inhibitors ciprofloxacin and levofloxacin brought therapeutic success.

Hafnia alvei pneumonia: a rare cause of infection in the multimorbid or immunocompromised.

Hafnia alvei is a rare, poorly understood commensal bacterium which has, on occasion, been shown to infect humans. We present two cases. The first patient presented with a 1-week history of dyspnoea, pleurisy and a productive cough, and the second with a prodrome of fatigue and night sweats. The former had a history of severe chronic obstructive pulmonary disease and the latter had a history of Crohn's disease. Both patients had underlying comorbidities and immunosuppression, but differed in presentation, radiological findings and recovery. This case series aims to remind readers of the broad differential of pathogens that can lead to disease in the immunocompromised and that one should not dismiss atypical cultured bacteria as commensal too hastily.

Reactive arthritis secondary to Hafnia alvei enterocolitis.

Diagnosis of postenteritic reactive arthritis (ReA) is a challenge and might have a broad range of differential diagnoses. A 50-year-old man was referred to our attention because of persistent inflammatory low back pain and asymmetric oligoarthritis. The clinical history was positive for diarrhoea in the previous 3 months. Inflammatory bowel disease, Whipple and celiac diseases were carefully excluded. In addition, serology, stool cultures, biopsies from the upper gastrointestinal tract yielded negative results for infections. A presumptive diagnosis of ReA was done and a non-steroidal anti-inflammatory drug trial prescribed. Persistence of symptoms prompted us for a second look of the colon. Biopsy collected from the terminal ileum were cultured and surprisingly colonies of Hafnia alvei, a rod-shaped Enterobacteriaceae, were detected. Treatment with ciprofloxacin leads to fast symptoms resolution. Although enterocolitis from H. alvei has been rarely reported, the culture of intestinal specimens might be recommended in the work-up of patients with suspected postenteritic ReA.

Hafnia alvei: uma revisão sistemática de literatura / Hafnia alvei: a review systems of literature

A presença de Enterobacteriaceae indica a qualidade higiênica dos produtos alimentícios. Dentro do grupo das bactérias que fazem parte dessa família está Hafnia alvei. Estudo bibliométrico é uma importante ferramenta metodológica de revisão sistemática para reunir e sintetizar as diversas informações que surgem sobre um tema, inclusive sobre os estudos relativos a micro- -organismos. O objetivo deste trabalho foi realizar um estudo bibliométrico sobre este agente. Para tal foi utilizada a base de dados Web of Science usando o nome do agente e o termo food para a busca e limitando a pesquisa entre 2007 e 2017. As informações principais dos documentos foram registradas, bem como a característica principal das publicações sobre o tema. Foram encontrados 42 artigos científicos que contemplaram os termos de busca. A maioria das publicações ocorreu em países e períodos onde ocorreram surtos alimentares e há uma grande pesquisa relacionada à genoma e resistência a antimicrobianos. Avalia-se que ainda existem várias oportunidades de pesquisa sobre os micro-organismos, visto que eles são pouco estudados, principalmente em nosso país.

The presence of Enterobacteriaceae indicates the hygienic quality of food products. As a part of this family, there is an emergent pathogen: Hafnia alvei. Bibliometrics appears as an important tool to gather and synthesize all the information that appears about the new microorganisms. The objective of this paper is to perform a systematic review of literature with bibliometric analysis in order to know the evolution of these bacteria and seek opportunities for new research. To do this, the Web of Science database was searched, individually searching for Hafnia alvei refining for "food". The articles found were analyzed from the annual production, countries, institutions, areas of knowledge, authors who produced the most and periodicals most used. A total of 42 articles were selected for Hafnia alvei. Most publications have occurred in countries and periods where there have been food outbreaks and there is great genomerelated research and antimicrobial resistance. It is evaluated that there are still several research opportunities on microorganisms, since they are little studied, mainly in our country.

Interactions of bacteriophage T4 adhesin with selected lipopolysaccharides studied using atomic force microscopy.

The interaction between the T4 bacteriophage gp37 adhesin and the bacterial lipopolysaccharide (LPS) is a well-studied system, however, the affinity and strength of the interaction haven't been analyzed so far. Here, we use atomic force microscopy to determine the strength of the interaction between the adhesin and its receptor, namely LPS taken from a wild strain of E. coli B. As negative controls we used LPSs of E. coli O111:B and Hafnia alvei. To study the interaction an AFM tip modified with the gp37 adhesin was used to scan surfaces of mica covered with one of the three different LPSs. Using the correlation between the surface topography images and the tip-surface interaction we could verify the binding between the specific LPS and the tip in contrast to the very weak interaction between the tip and the non-binding LPSs. Using force spectroscopy we could then measure the binding strength by pulling on the AFM tip until it lifted off from the surface. The force necessary to break the interaction between gp37 and LPS from E. coli B, LPS from E. coli O111:B and LPS from H. alvei were measured to be 70 ± 29 pN, 46 ± 13 pN and 45 ± 14 pN, respectively. The latter values are likely partially due to non-specific interaction between the gp37 and the solid surface, as LPS from E. coli O111:B and LPS from H. alvei have been shown to not bind to gp37, which is confirmed by the low correlation between binding and topography for these samples.

Endocarditis infecciosa en válvula nativa mitral por Hafnia alvei / Infective endocarditis in native mitral valve by Hafnia alvei

We report the case of a 40-year-old male patient with no prior personal pathological history, who had a prolonged febrile syndrome without being associated with other important clinical features. He was diagnosed with subacute bacterial endocarditis in the native mitral valve by an atypical pathogen: Hafnia Alvei. After an exhaustive review of the bibliography of the last 20 years corresponding to the Cuban medical journals, we conclude that we are facing the first clinical case of this type published in Cuba(AU)

Se presenta el caso clínico de un paciente masculino de 40 años de edad, sin antecedentes patológicos personales, portador de un síndrome febril prolongado sin asociarse a otros elementos clínicos de importancia. Se le diagnosticó una endocarditis bacteriana subaguda en válvula mitral nativa por un germen patógeno atípico: Hafnia alvei. Tras realizar una exhaustiva revisión de la bibliografía de los últimos 20 años correspondiente a las revistas médicas cubanas, se concluye que estamos frente al primer caso clínico de este tipo publicado en Cuba(AU)

Inhibition of Low-Grade Inflammation by Anthocyanins after Microbial Fermentation in Vitro.

The anti-inflammatory effects of anthocyanins (ACNs) on vascular functions are discussed controversially because of their low bioavailability. This study was performed to determine whether microorganism (MO)-fermented ACNs influence vascular inflammation in vitro. Therefore, MO growth media were supplemented with an ACN-rich grape/berry extract and growth responses of Escherichia coli, E. faecalis and H. alvei, as well as ACN fermentation were observed. MO supernatants were used for measuring the anti-inflammatory effect of MO-fermented ACNs in an epithelial-endothelial co-culture transwell system. After basolateral enrichment (240 min), endothelial cells were stimulated immediately or after 20 h with TNF-α. Afterwards, leukocyte adhesion, expression of adhesion molecules and cytokine release were measured. Results indicate that E. coli, E. faecalis and H. alvei utilized ACNs differentially concomitant with different anti-inflammatory effects. Whereas E. coli utilized ACNs completely, no anti-inflammatory effects of fermented ACNs were observed on activated endothelial cells. In contrast, ACN metabolites generated by E. faecalis and H. alvei significantly attenuated low-grade stimulated leukocyte adhesion, the expression of adhesion molecules E-selectin, VCAM-1 and ICAM-1 and cytokine secretion (IL-8 and IL-6), as well as NF-κB mRNA expression with a more pronounced effect of E. faecalis than H. alvei. Thus, MO-fermented ACNs have the potential to reduce inflammation.

Elaboration of highly hydrophobic polymeric surface--a potential strategy to reduce the adhesion of pathogenic bacteria?

Different polymeric surfaces have been modified in order to reach a high hydrophobic character, indeed the superhydrophobicity property. For this purpose, polypropylene and polystyrene have been treated by RF or µwaves CF4 plasma with different volumes, the results were compared according to the density of injected power. The effect of pretreatment such as mechanical abrasion or plasma activation was also studied. The modified surfaces were shown as hydrophobic, or even superhydrophobic depending of defects density. They were characterized by measurement of wettability and roughness at different scales, i.e. macroscopic, mesoscopic and atomic. It has been shown that a homogeneous surface at the macroscopic scale could be heterogeneous at lower mesoscopic scale. This was associated with the crystallinity of the material. The bioadhesion tests were performed with Gram positive and negative pathogenic strains: Listeria monocytogenes, Pseudomonas aeruginosa and Hafnia alvei. They have demonstrated an antibacterial efficiency of very hydrophobic and amorphous PS treated for all strains tested and a strain-dependent efficiency with modified PP surface being very heterogeneous at the mesoscopic scale. Thus, these biological results pointed out not only the respective role of the surface chemistry and topography in bacterial adhesion, but also the dependence on the peaks and valley distribution at bacteria dimension scale.

Degradation of phytate by the 6-phytase from Hafnia alvei: a combined structural and solution study.

Phytases hydrolyse phytate (myo-inositol hexakisphosphate), the principal form of phosphate stored in plant seeds to produce phosphate and lower phosphorylated myo-inositols. They are used extensively in the feed industry, and have been characterised biochemically and structurally with a number of structures in the PDB. They are divided into four distinct families: histidine acid phosphatases (HAP), ß-propeller phytases, cysteine phosphatases and purple acid phosphatases and also split into three enzyme classes, the 3-, 5- and 6-phytases, depending on the position of the first phosphate in the inositol ring to be removed. We report identification, cloning, purification and 3D structures of 6-phytases from two bacteria, Hafnia alvei and Yersinia kristensenii, together with their pH optima, thermal stability, and degradation profiles for phytate. An important result is the structure of the H. alvei enzyme in complex with the substrate analogue myo-inositol hexakissulphate. In contrast to the only previous structure of a ligand-bound 6-phytase, where the 3-phosphate was unexpectedly in the catalytic site, in the H. alvei complex the expected scissile 6-phosphate (sulphate in the inhibitor) is placed in the catalytic site.

[Report of four clinical cases of Hafnia alvei bacteremia in a pediatric cardiac surgery unit]. / Reporte de cuatro casos clínicos de bacteriemia por Hafnia alvei en una unidad cardio-quirúrgica pediátrica.

INTRODUCTION: The gram-negative bacillus Hafnia alvei is the only species of the genus Hafnia, family Enterobacteriaceae. It occasionally behaves as an opportunistic pathogen in humans, causing intestinal and respiratory infection and sepsis. It rarely causes bacteremia, usually of unknown focus. OBJECTIVE: To describe a nosocomial outbreak of four pediatric patients with bacteremia by Hafnia alvei. METHODS: Descriptive study using clinical records of pediatric patients diagnosed with Hafnia alvei bacteremia in a pediatric cardio surgical unit, in October 2008. RESULTS: The attack rate was 4/8 (50%), lethality rate 2/4 (50%) and mortality 2/8 (25%). The microbiological study and pulsed-field gel electrophoresis confirmed the same clonal bacterial strain. DISCUSSION: The source of bacteremia was identified only in two patients and was associated with central venous catheters. The other two cases had no known infectious source. Epidemiological surveillance of emerging agents must be maintained.

Reporte de cuatro casos clínicos de bacteriemia por Hafnia alvei en una unidad cardio-quirúrgica pediátrica / Report of four clinical cases of Hafnia alvei bacteremia in a pediatric cardiac surgery unit

Introduction: The gram-negative bacillus Hafnia alvei is the only species of the genus Hafnia, family Enterobacteriaceae. It occasionally behaves as an opportunistic pathogen in humans, causing intestinal and respiratory infection and sepsis. It rarely causes bacteremia, usually of unknown focus. Objective: To describe a nosocomial outbreak of four pediatric patients with bacteremia by Hafnia alvei. Methods: Descriptive study using clinical records of pediatric patients diagnosed with Hafnia alvei bacteremia in a pediatric cardio surgical unit, in October 2008. Results: The attack rate was 4/8 (50 percent), lethality rate 2/4 (50 percent) and mortality 2/8 (25 percent). The microbiological study and pulsed-field gel electrophoresis confirmed the same clonal bacterial strain. Discussion: The source of bacteremia was identified only in two patients and was associated with central venous catheters. The other two cases had no known infectious source. Epidemiological surveillance of emerging agents must be maintained.

Introducción: Hajhia alvei, bacilo Gram negativo, constituye la única especie del género Hajhia, familia Enterobacteriaceae. En el humano se comporta ocasionalmente como oportunista produciendo infección intestinal, respiratoria y sepsis. Es causa infrecuente de bacteriemias, generalmente de foco infeccioso desconocido. Objetivo: Describir un brote intrahospitalario de cuatro pacientes pediátricos con bacteriemias por Hajhia alvei. Método: Estudio descriptivo retrospectivo de los registros clínicos de cuatro pacientes pediátricos con diagnóstico de bacte-riemia por Hajhia alvei en una unidad cardioquirúrgica pediátrica identificados en octubre del 2008. Resultados: La tasa de ataque fue 4/8 (50 por ciento), tasa de letalidad 2/4 (50 por ciento) y de mortalidad de 2/8 (25 por ciento). El estudio micro-biológico y la electroforesis de campo pulsado confirman la misma cepa bacteriana clonal. Discusión: Se identificó el origen de la bacteriemia sólo en dos pacientes asociado a catéter venoso central. Los otros dos casos no tuvieron foco infeccioso conocido. Se debe mantener vigilancia epidemiológica de agentes emergentes.

Inhibition of the early stage of Salmonella enterica serovar Enteritidis biofilm development on stainless steel by cell-free supernatant of a Hafnia alvei culture.

Compounds present in Hafnia alvei cell-free culture supernatant cumulatively negatively influence the early stage of biofilm development by Salmonella enterica serovar Enteritidis on stainless steel while they also reduce the overall metabolic activity of S. Enteritidis planktonic cells. Although acylhomoserine lactones (AHLs) were detected among these compounds, the use of several synthetic AHLs was not able to affect the initial stage of biofilm formation by this pathogen.

[Aberrant gallstones--extraordinary complications of laparoscopic cholecystectomy]. / Gallensteine auf Abwegen - Ungewöhnliche Komplikationen der laparoskopischen Cholezystektomie.

About 0.2 % of patients undergoing laparoscopic cholecystetomy will suffer from complications caused by lost gallstones. Diagnostic and therapeutic measures are correlated to the symptoms. At different locations, abscesses can arise, which can be treated by direct access through the -abdominal wall, laparotomy or laparoscopy. Two cases are presented with the especially grave sequels of subphrenic abscess, infiltration of the thoracic wall, and pleural empyema, which -respectively needed several successive operations -after ten years. In laparoscopic cholecystectomy, all detected stones should be removed. In the case of a failure, conversion to laparotomy is not essential. The loss of stones has to be formally -documented, the patient and family doctor are to be informed.

Biofilm formation and acyl homoserine lactone production in Hafnia alvei isolated from raw milk

The objective of this study was to detect the presence of acyl homoserine lactones (AHLs), signal molecules of the quorum sensing system in biofilm formed by Hafnia alvei strains. It also evaluated the effect of synthetic quorum sensing inhibitors in biofilm formation. AHLs were assayed using well diffusion techniques, thin layer chromatography (TLC) and detection directly in biofilm with biomonitors. The extracts obtained from planktonic and sessile cell of H. alvei induced at least two of three monitor strains evaluated. The presence of AHLs with up to six carbon atoms was confirmed by TLC. Biofilm formation by H. alvei was inhibited by furanone, as demonstrated by 96-well assay of crystal violet in microtitre plates and by scanning electron microscopy. The H. alvei 071 hall mutant was deficient in biofilm formation. All these results showed that the quorum sensing system is probably involved in the regulation of biofilm formation by H. alvei.

[The analysis of the bacterial and fungal flora in maxillary sinuses in patients operated due to FESS method]. / Analiza flory bakteryjnej i grzybiczej zatok szczqkowych u chorych operowanych metoda FESS.

INTRODUCTION: The aim of this work was to analyse the bacterial and fungal flora in maxillary sinuses in patients operated due to the FESS method. MATERIAL AND METHODS: Studies were conducted on 110 patients, including 47 women aged 17-78 and 63 men aged 17-66, who underwent endoscopic surgical procedures due to chronic polypoid maxillary sinusitis between 2006 and 2007. 214 cultures were prepared altogether. During the endoscopic operation on paranasal sinuses, a cannula was introduced along the natural entrance and material for the culture and antibiogram was removed by suction. RESULTS: In the studied material of 214 cultures, 72 (33.6%) cultures obtained positive results, including 2 cases with bacterial and fungal floras present simultaneously (Aspergillus fumigatus and Aspergillus niger) in 38 operated patients. In 25 (34.5%) cultures we noted the presence of Staphylococcus epidermidis, which was sensitive to the following antibiotics: Cotrimoxazole, Rifampicin, Vankomycin, Teicoplanin and Levofloxacin. Staphylococcus epidermidis was isolated in 22 (31.0%) cultures, showing 100% sensitivity to similar antibiotics like the previous one. Another bacteria (Escherichia coli) was cultured in 10 cultures (13.8%), in 70% of the cases every second bacteria was Staphylococcus epidermidis with 100% sensitivity mainly to cephalosporins and aminoglycosides. In 3 cultures (4.17%) we found Klebsiella pneumoniae, with 100% sensitivity to cephalosporins and aminoglycosides and 100% resistance to penicillins. In three cases Pseudomonas fluorescens and Proteus mirabilis (4.17% each) were cultured with their sensitivity and resistance similar to those of Klebsiella pneumoniae. Two cases (2.8% each) in the cultures were noted: Citrobacter freundii, Streptococcus oralis and Hafnia alvei, which were 100% sensitive to some cephalosporins and aminoglycosides whereas their resistance to penicillins and Cefuroxime was as high as 100%. CONCLUSION: In the operated patients suffering from chronic polypoid maxillary sinuses we found 33.6% of positive results in the bacterial flora. This indicates that the changes were accompanied by an acute inflammatory condition, thus surgical procedures had to be followed by a guided antibiotic. The cultured bacteria demonstrated sensitivity to some cephalosporins and aminoglycosides and resistance to penicillins, which proves the abuse of penicillins in the treatment of acute inflammatory states of upper airways.

Escherichia albertii and Hafnia alvei are candidate enteric pathogens with divergent effects on intercellular tight junctions.

Attaching-effacing lesion-inducing Escherichia albertii and the related, but non-attaching-effacing organism, Hafnia alvei, are both implicated as enteric pathogens in humans. However, effects of these bacteria on epithelial cells are not well-characterized. Related enteropathogens, including enterohemorrhagic Escherichia coli O157:H7, decrease epithelial barrier function by disrupting intercellular tight junctions in polarized epithelia. Therefore, this study assessed epithelial barrier function and tight junction protein distribution in polarized epithelia following bacterial infections. Polarized epithelial (MDCK-I and T84) cells grown on filter supports were infected apically with E. coli O157:H7, E. albertii, and H. alvei for 16h at 37 degrees C. All strains decreased transepithelial electrical resistance and increased permeability to a dextran probe in a host cell-dependent manner. Immunofluorescence microscopy showed that both E. coli O157:H7 and E. albertii, but not H. alvei, caused a redistribution of the tight junction protein zona occludens-1. In contrast to E. coli O157:H7, E. albertii and H. alvei did not redistribute claudin-1. Western blotting of whole cell protein extracts demonstrated that each bacterium caused differential changes in tight junction protein expression, dependent on the host cell. These findings demonstrate that E. albertii and H. alvei are candidate enteric pathogens that have both strain-specific and host epithelial cell-dependent effects.